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<H2> Table of Contents
</H2>

<PRE>
   <A HREF="#NAIF Integer ID codes">NAIF Integer ID codes</A>
      <A HREF="#Revisions">Revisions</A>
      <A HREF="#Abstract">Abstract</A>
      <A HREF="#Introduction">Introduction</A>
      <A HREF="#Use of Code-to-Name/Name-to-Code Mappings from SPICE">Use of Code-to-Name/Name-to-Code Mappings from SPICE</A>
         <A HREF="#Use of an External Mapping Definition Kernel">Use of an External Mapping Definition Kernel</A>
         <A HREF="#Masking">Masking</A>
      <A HREF="#NAIF Object ID numbers">NAIF Object ID numbers</A>
         <A HREF="#Barycenters">Barycenters</A>
         <A HREF="#Planets and Satellites">Planets and Satellites</A>
         <A HREF="#Spacecraft">Spacecraft</A>
         <A HREF="#Earth Orbiting Spacecraft.">Earth Orbiting Spacecraft.</A>
         <A HREF="#Comet Shoemaker Levy 9">Comet Shoemaker Levy 9</A>
         <A HREF="#Comets">Comets</A>
         <A HREF="#Asteroids">Asteroids</A>
         <A HREF="#Ground Stations.">Ground Stations.</A>
         <A HREF="#Inertial and Non-inertial Reference Frames">Inertial and Non-inertial Reference Frames</A>
      <A HREF="#Spacecraft Clocks.">Spacecraft Clocks.</A>
      <A HREF="#Instruments">Instruments</A>

</PRE>

<HR SIZE=3 NOSHADE>

<BR><BR>
<A NAME="NAIF Integer ID codes"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H1> NAIF Integer ID codes
</H1><HR SIZE=3 NOSHADE><P><BR><BR><BR>
<BR><BR>
<A NAME="Revisions"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Revisions
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   Last revised on 2010 MAY 20 by E. D. Wright.
<P>
 
   This version of the document supersedes all previous versions.
<P>
 
<BR><BR>
<A NAME="Abstract"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Abstract
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   The NAIF IDS required reading lists all default ID-name mappings for the
   SPICE toolkits and a description of functionality of the corresponding
   software.
<P>
 
<BR><BR>
<A NAME="Introduction"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Introduction
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   SPICE system kernel files and subroutines refer to ephemeris objects,
   reference frames, and instruments by integer codes.
<P>
 
   An ephemeris object is any object that may have ephemeris or trajectory
   data such as a planet, natural satellite, tracking station, spacecraft,
   barycenter (the center of mass of a group of bodies), asteroid, or
   comet. Each body in the solar system is associated with an integer code
   for use with SPICE. The names and codes for many of these objects are
   listed below.
<P>
 
   Spacecraft ID codes are negative. These ID codes are usually derived
   from NASA control authority assignments. Instruments mounted on
   spacecraft also have ID codes. These are determined by multiplying the
   spacecraft ID by 1000 and subtracting the ordinal number of the
   instrument from the resulting product. Thus we can algorithmically
   recover the spacecraft code from an instrument code, and each instrument
   may have a unique code as long as there are 999 or fewer on a
   spacecraft.
<P>
 
   Caution: the NASA spacecraft ID control authority at GSFC is forced into
   reusing some IDs. This can affect the SPICE system for planetary or
   other spacecraft for which ID-name mappings are registered. (Here
   "registered" means a spacecraft for which use of the SPICE system is an
   actuality, or was contemplated.) Three cases exist.
<P>
 
<UL>
<TT>1.</TT> This document and ID-to-name mapping software include both past and current
ID-name mappings for cases where both the old and the new ID assignments
are for spacecraft registered within SPICE. The last mentioned ID-to-name
mapping in this document is the one that will be used in SPICE software to
effect ID-to-name translations within SPICE-based code.
<BR><BR></UL>
<UL>
<TT>2.</TT> This document and ID-to-name mapping software contain only a mapping for
the current use of a given ID if prior uses involved spacecraft never
registered with SPICE (e.g. many non-planetary missions).
<BR><BR></UL>
<UL>
<TT>3.</TT> This document and ID-to-name mapping software contain only a mapping for a
prior use of a given ID if that prior use was for a spacecraft registered
within SPICE and current use of the ID is for a spacecraft not registered
within SPICE.
<BR><BR></UL>
   For spacecraft the ID-to-name mapping may be a one-to-many mapping,
   allowing two or more names for a spacecraft to exist for a single
   numeric ID. The last mentioned ID-to-name mapping in this document is
   the one that will be used in SPICE software to effect ID-to-name
   translations within SPICE-based code.
<P>
 
   As the reader will see, ID codes now show the wear that results from an
   expanding system. As the SPICE system has expanded so has the number of
   objects that require identifying codes. Many of these objects do not fit
   neatly into the schemes originally envisioned as needing ID codes. As a
   result, the current system is a bit eclectic.
<P>
 
<BR><BR>
<A NAME="Use of Code-to-Name/Name-to-Code Mappings from SPICE"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Use of Code-to-Name/Name-to-Code Mappings from SPICE
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   Software exists within the SPICE system that allows a user to easily map
   between an integer code and the object name that code represents or
   vice-versa.
<P>
 
   <a href="../cspice/bodc2n_c.html">bodc2n_c</a> performs the integer code to name mapping; input a code, the
   routine returns the corresponding name:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( code, lenout, &amp;name, &amp;found );
 
      Where ``lenout'' defines the maximum string length for name.
</PRE>
   <a href="../cspice/bodn2c_c.html">bodn2c_c</a> performs the name to integer code mapping; input a name, the
   routine returns the corresponding ID code:
<P>
 
<PRE>
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( name, &amp;code, &amp;found );
</PRE>
   <a href="../cspice/boddef_c.html">boddef_c</a> performs a run-time assignment of a name/code mapping for later
   translation by <a href="../cspice/bodc2n_c.html">bodc2n_c</a> and <a href="../cspice/bodn2c_c.html">bodn2c_c</a>:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( name, code );
</PRE>
   with `name' defining the character string associated with integer
   `code'. When using <a href="../cspice/bodn2c_c.html">bodn2c_c</a>, the `name' look-up is case insensitive,
   left justified, and space compressed (multiple spaces between words
   reduced to one) format. Spaces between words are significant.
<P>
 
<PRE>
      These strings are equivalent:
         'EARTH', '  Earth ', 'earth  '
      As well as:
         'Solar System Barycenter', 'SOLAR  System  barycenter'
      but
         'SolarSystemBarycenter'
      is not due to the lack of spaces between words.
</PRE>
   The boolean `found' has value true if a mapping look-up succeeded, false
   otherwise.
<P>
 
<BR><BR>
<A NAME="Use of an External Mapping Definition Kernel"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Use of an External Mapping Definition Kernel
</H3><P><BR><BR>
   If necessary, a user may elect to load additional name-ID pairs for
   access by SPICE software. These pairs may be new definitions, or they
   may override the default mapping assignment.
<P>
 
   Create new name-ID pairs With a text kernel such as
<P>
 
<PRE>
      \begintext
 
      Define an additional set of body, ID code mappings.
 
      \begindata
 
      NAIF_BODY_CODE  += ( 22, 23, 24, 25 )
 
      NAIF_BODY_NAME  += ( 'LARRY', 'MOE', 'CURLEY', 'SHEMP' )
</PRE>
   Load the kernel as usual with a <a href="../cspice/furnsh_c.html">furnsh_c</a> call. The names defined in
   NAIF_BODY_NAME map to the corresponding index of NAIF_BODY_CODE, i.e.
   LARRY-&gt;22, MOE-&gt;23, etc, and the IDs in NAIF_BODY_CODE map to the
   corresponding index of NAIF_BODY_NAME.
<P>
 
   If an external ID kernel is used, be aware of several rules:
<P>
 
<UL>
<TT>1.</TT> All ID codes MUST be listed in the kernel variable NAIF_BODY_CODE, and all
names MUST be listed in the kernel variable NAIF_BODY_NAME.
<BR><BR></UL>
<UL>
<TT>2.</TT> The CSPICE system can access 2000 external name-ID pairs defined via a text
kernel. CSPICE signals an error when the number of assignments exceeds
2000.
<BR><BR></UL>
<UL>
<TT>3.</TT> You may assign an ID code to multiple names. A <a href="../cspice/bodc2n_c.html">bodc2n_c</a> call returns the
last name assigned; a last in, first out situation.
<BR><BR></UL>
   Since NAIF_BODY_CODE and NAIF_BODY_NAME are kernel variables, use of the
   "+=" notation in the previous example means the values are appended to
   the mapping set present in memory. For example, the block:
<P>
 
<PRE>
      \begindata
 
      NAIF_BODY_CODE  += ( 170100, 170101 )
 
      NAIF_BODY_NAME  += ( 'Enterprise', 'Enterprise-A' )
</PRE>
   appends the two pairings to the existent set of mappings.
<P>
 
   CAUTION: Use of the assignment operator, ''='', instead of the append
   operator, ''+='', destroys any previous name-ID definitions for a kernel
   variable.
<P>
 
<BR><BR>
<A NAME="Masking"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Masking
</H3><P><BR><BR>
   As of release N53, the SPICE Toolkit provides the user the functionality
   to override or mask any name/ID mapping. Use a <a href="../cspice/boddef_c.html">boddef_c</a> call or define
   NAIF_BODY_NAME, NAIF_BODY_CODE assignments from a text kernel to perform
   a masking operations. Simplistically, the mask functionality provides
   the user the option of mapping multiple names to the same code.
<P>
 
   Name/ID assignments function within a precedence hierarchy, so a lower
   precedence operation cannot affect previous assignments created by an
   operation of higher precedence. Kernel pool definitions have the highest
   precedence, <a href="../cspice/boddef_c.html">boddef_c</a> definitions next, and finally the default
   definitions. The order of assignments is significant.
<P>
 
<PRE>
                                    Highest precedence
 
                                   (1) Kernel pool final assignment
 
                             (2) Kernel pool initial assignment
 
                       (3) A ``boddef'' call final assignment
 
                 (4) A ``boddef'' call initial assignment
 
           (5) The default mappings final assignment
 
     (6) The default mappings initial assignment
 
     Lowest precedence
</PRE>
   Example 1:
<P>
 
   Assign the name 'x' (lower case) to ID 1000 with <a href="../cspice/boddef_c.html">boddef_c</a>:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( "x", 1000 );
</PRE>
   A call to <a href="../cspice/bodc2n_c.html">bodc2n_c</a> with 1000 as the input ID:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( 1000, lenout, &amp;name, &amp;found );
</PRE>
   returns the name 'x'. The <a href="../cspice/bodn2c_c.html">bodn2c_c</a> calls:
<P>
 
<PRE>
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( "x", &amp;code, &amp;found );
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( "X", &amp;code, &amp;found );
</PRE>
   both return the ID as 1000. Note the case insensitivity of the name
   input.
<P>
 
   Now a demo of simple masking functionality. Assign a new name to ID
   1000:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( "Y", 1000 );
</PRE>
   so the <a href="../cspice/bodn2c_c.html">bodn2c_c</a> call
<P>
 
<PRE>
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( "Y", &amp;code, &amp;found );
</PRE>
   returns an ID of 1000. In a similar manner, the <a href="../cspice/bodc2n_c.html">bodc2n_c</a> call:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( 1000, lenout, &amp;name, &amp;found );
</PRE>
   returns the name 'Y'. Still, the code assigned to 'x' persists within
   CSPICE as the call:
<P>
 
<PRE>
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( "x", &amp;code, &amp;found );
</PRE>
   also returns ID 1000. If we reassign 'Y' to a different ID:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( "Y", 1001 );
</PRE>
   then make a <a href="../cspice/bodc2n_c.html">bodc2n_c</a> call with 1000 as the input ID:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( 1000, lenout, &amp;name, &amp;found );
</PRE>
   the routine returns the name 'x'. We assigned an ID to 'x', masked it
   with another name, then demasked it by reassigning the masking name,
   'Y'.
<P>
 
   If a <a href="../cspice/boddef_c.html">boddef_c</a> assigns an existing name to an existing code, that
   assignment takes precedence.
<P>
 
   Example 2:
<P>
 
<PRE>
      <a href="../cspice/bodn2c_c.html">bodn2c_c</a>( "THEBE", &amp;code, &amp;found );
</PRE>
   returns a code value 514. Likewise
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( 514, &amp;name, &amp;found );
</PRE>
   returns a name of 'THEBE'. Yet the name '1979J2' also maps to code 514,
   but with lower precedence.
<P>
 
   The <a href="../cspice/boddef_c.html">boddef_c</a> call:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( "1979J2", 514 );
</PRE>
   places the '1979J2' &lt;-&gt; 514 mapping at the top of the precedence
   list, so:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( 514, &amp;name, &amp;found );
</PRE>
   returns the name '1979J2'. Note, 'THEBE' still resolves to 514.
<P>
 
   In those cases where a kernel pool assignment overrides a <a href="../cspice/boddef_c.html">boddef_c</a>, the
   <a href="../cspice/boddef_c.html">boddef_c</a> mapping 'reappears' when an unload_c, kclear_c or <a href="../cspice/clpool_c.html">clpool_c</a> call
   clears the kernel pool mappings.
<P>
 
   Example 3:
<P>
 
   Execute a <a href="../cspice/boddef_c.html">boddef_c</a> call:
<P>
 
<PRE>
      <a href="../cspice/boddef_c.html">boddef_c</a>( "vehicle2", -1010 );
</PRE>
   A <a href="../cspice/bodc2n_c.html">bodc2n_c</a> call:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( -1010, lenout, &amp;name, &amp;found );
</PRE>
   returns the name 'vehicle2' as expected. If you then load the name/ID
   kernel body.ker:
<P>
 
<PRE>
      \begindata
 
      NAIF_BODY_NAME = ( 'vehicle1' )
      NAIF_BODY_CODE = ( -1010      )
 
      \begintext
</PRE>
   with <a href="../cspice/furnsh_c.html">furnsh_c</a>:
<P>
 
<PRE>
      <a href="../cspice/furnsh_c.html">furnsh_c</a>( "body.ker" );
</PRE>
   the <a href="../cspice/bodc2n_c.html">bodc2n_c</a> call:
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( -1010, lenout, &amp;name, &amp;found );
</PRE>
   returns 'vehicle1' since the kernel assignment take precedence over the
   <a href="../cspice/boddef_c.html">boddef_c</a> assignment.
<P>
 
   The name/ID map state:
<P>
 
<PRE>
       -1010    -&gt; vehicle1
       vehicle1 -&gt; -1010
       vehicle2 -&gt; -1010
</PRE>
   Now, unload the body kernel:
<P>
 
<PRE>
      <a href="../cspice/unload_c.html">unload_c</a>( "body.ker" );
</PRE>
   The <a href="../cspice/boddef_c.html">boddef_c</a> assignment resumes highest precedence.
<P>
 
<PRE>
      <a href="../cspice/bodc2n_c.html">bodc2n_c</a>( -1010, lenout, &amp;name, &amp;found );
</PRE>
   The call returns 'vehicle2' for the name.
<P>
 
   CAUTION: Please understand a <a href="../cspice/clpool_c.html">clpool_c</a> or <a href="../cspice/kclear_c.html">kclear_c</a> call deletes all
   mapping assignments defined through the kernel pool. No similar clear
   functionality exists to clear <a href="../cspice/boddef_c.html">boddef_c</a>. boddef_c assignments persist
   unless explicitly overridden.
<P>
 
<BR><BR>
<A NAME="NAIF Object ID numbers"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> NAIF Object ID numbers
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   In theory, a unique integer can be assigned to each body in the solar
   system, including interplanetary spacecraft. SPICE uses integer codes
   instead of names to refer to ephemeris bodies for three reasons.
<P>
 
<UL>
<TT>1.</TT> Space
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> Integer codes are smaller than alphanumeric names.
<BR><BR></UL>
<UL>
<TT>2.</TT> Uniqueness
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> The names of some satellites conflict with the names of some asteroids and
comets. Also, some satellites are commonly referred to by names other than
those approved by the IAU.
<BR><BR></UL>
<UL>
<TT>3.</TT> Context
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> The type of a body (barycenter, planet, satellite, comet, asteroid, or
spacecraft) and the system to which it belongs (Earth, Mars, Jupiter,
Saturn, Uranus, Neptune, or Pluto) can be recovered algorithmically from
the integer code assigned to a body. This is not generally true for names.
<BR><BR></UL>
<BR><BR>
<A NAME="Barycenters"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Barycenters
</H3><P><BR><BR>
   The smallest positive codes are reserved for the Sun and planetary
   barycenters:
<P>
 
<PRE>
      NAIF ID     NAME
      ________    ____________________
      0           'SSB'
      0           'SOLAR SYSTEM BARYCENTER'
      1           'MERCURY BARYCENTER'
      2           'VENUS BARYCENTER'
      3           'EMB'
      3           'EARTH MOON BARYCENTER'
      3           'EARTH-MOON BARYCENTER'
      3           'EARTH BARYCENTER'
      4           'MARS BARYCENTER'
      5           'JUPITER BARYCENTER'
      6           'SATURN BARYCENTER'
      7           'URANUS BARYCENTER'
      8           'NEPTUNE BARYCENTER'
      9           'PLUTO BARYCENTER'
      10          'SUN'
</PRE>
   For those planets without moons, Mercury and Venus, the barycenter
   location coincides with the body center of mass. However do not infer
   you may interchange use of the planet barycenter ID and the planet ID. A
   barycenter has no radii, right ascension/declination of the pole axis,
   etc. Use the planet ID when referring to a planet or any property of
   that planet.
<P>
 
<BR><BR>
<A NAME="Planets and Satellites"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Planets and Satellites
</H3><P><BR><BR>
   Planets have ID codes of the form P99, where P is 1, ..., 9 (the
   planetary ID); a planet is always considered to be the 99th satellite of
   its own barycenter, e.g. Jupiter is body number 599. Natural satellites
   have ID codes of the form
<P>
 
<PRE>
           PNN, where
 
                  P  is  1, ..., 9
              and NN is 01, ... 98
</PRE>
   or
<P>
 
<PRE>
           PXNNN, where
 
                  P   is    1, ...,  9,
                  X   is    0  or    5,
              and NNN is  001, ... 999
 
        Codes with X = 5 are provisional.
</PRE>
   e.g. Ananke, the 12th satellite of Jupiter (JXII), is body number 512.
   (Note the fragments of comet Shoemaker Levy 9 are exceptions to this
   rule.)
<P>
 
<PRE>
      NAIF ID     NAME                    IAU NUMBER
      ________    ____________________    __________
      199         'MERCURY'
      299         'VENUS'
      399         'EARTH'
      301         'MOON'
      499         'MARS'
      401         'PHOBOS'                MI
      402         'DEIMOS'                MII
      599         'JUPITER'
      501         'IO'                    JI
      502         'EUROPA'                JII
      503         'GANYMEDE'              JIII
      504         'CALLISTO'              JIV
      505         'AMALTHEA'              JV
      506         'HIMALIA'               JVI
      507         'ELARA'                 JVII
      508         'PASIPHAE'              JVIII
      509         'SINOPE'                JIX
      510         'LYSITHEA'              JX
      511         'CARME'                 JXI
      512         'ANANKE'                JXII
      513         'LEDA'                  JXIII
      514         'THEBE'                 JXIV
      515         'ADRASTEA'              JXV
      516         'METIS'                 JXVI
      517         'CALLIRRHOE'            JXVII
      518         'THEMISTO'              JXVIII
      519         'MAGACLITE'             JXIX
      520         'TAYGETE'               JXX
      521         'CHALDENE'              JXXI
      522         'HARPALYKE'             JXXII
      523         'KALYKE'                JXXIII
      524         'IOCASTE'               JXXIV
      525         'ERINOME'               JXXV
      526         'ISONOE'                JXXVI
      527         'PRAXIDIKE'             JXXVII
      528         'AUTONOE'               JXXVIII
      529         'THYONE'                JXXIX
      530         'HERMIPPE'              JXXX
      531         'AITNE'                 JXXXI
      532         'EURYDOME'              JXXXII
      533         'EUANTHE'               JXXXIII
      534         'EUPORIE'               JXXXIV
      535         'ORTHOSIE'              JXXXV
      536         'SPONDE'                JXXXVI
      537         'KALE'                  JXXXVII
      538         'PASITHEE'              JXXXVIII
      539         'HEGEMONE'
      540         'MNEME'
      541         'AOEDE'
      542         'THELXINOE'
      543         'ARCHE'
      544         'KALLICHORE'
      545         'HELIKE'
      546         'CARPO'
      547         'EUKELADE'
      548         'CYLLENE'
      549         'KORE'
      550         'HERSE'
      699         'SATURN'
      601         'MIMAS'                 SI
      602         'ENCELADUS'             SII
      603         'TETHYS'                SIII
      604         'DIONE'                 SIV
      605         'RHEA'                  SV
      606         'TITAN'                 SVI
      607         'HYPERION'              SVII
      608         'IAPETUS'               SVIII
      609         'PHOEBE'                SIX
      610         'JANUS'                 SX
      611         'EPIMETHEUS'            SXI
      612         'HELENE'                SXII
      613         'TELESTO'               SXIII
      614         'CALYPSO'               SXIV
      615         'ATLAS'                 SXV
      616         'PROMETHEUS'            SXVI
      617         'PANDORA'               SXVII
      618         'PAN'                   SXVIII
      619         'YMIR'                  SXIX
      620         'PAALIAQ'               SXX
      621         'TARVOS'                SXXI
      622         'IJIRAQ'                SXXII
      623         'SUTTUNGR'              SXXIII
      624         'KIVIUQ'                SXXIV
      625         'MUNDILFARI'            SXXV
      626         'ALBIORIX'              SXXVI
      627         'SKATHI'                SXXVII
      628         'ERRIAPUS'              SXXVIII
      629         'SIARNAQ'               SXXIX
      630         'THRYMR'                SXXX
      631         'NARVI'                 SXXXI
      632         'METHONE'               SXXXII
      633         'PALLENE'               SXXXIII
      634         'POLYDEUCES'            SXXXIV
      635         'DAPHNIS'
      636         'AEGIR'
      637         'BEBHIONN'
      638         'BERGELMIR'
      639         'BESTLA'
      640         'FARBAUTI'
      641         'FENRIR'
      642         'FORNJOT'
      643         'HATI'
      644         'HYROKKIN'
      645         'KARI'
      646         'LOGE'
      647         'SKOLL'
      648         'SURTUR'
      649         'ANTHE'
      650         'JARNSAXA'
      651         'GREIP'
      652         'TARQEQ'
      653         'AEGAEON'
 
      799         'URANUS'
      701         'ARIEL'                 UI
      702         'UMBRIEL'               UII
      703         'TITANIA'               UIII
      704         'OBERON'                UIV
      705         'MIRANDA'               UV
      706         'CORDELIA'              UVI
      707         'OPHELIA'               UVII
      708         'BIANCA'                UVIII
      709         'CRESSIDA'              UIX
      710         'DESDEMONA'             UX
      711         'JULIET'                UXI
      712         'PORTIA'                UXII
      713         'ROSALIND'              UXIII
      714         'BELINDA'               UXIV
      715         'PUCK'                  UXV
      716         'CALIBAN'               UXVI
      717         'SYCORAX'               UXVII
      718         'PROSPERO'              UXVIII
      719         'SETEBOS'               UXIX
      720         'STEPHANO'              UXX
      721         'TRINCULO'              UXXI
      722         'FRANCISCO'
      723         'MARGARET'
      724         'FERDINAND'
      725         'PERDITA'
      726         'MAB'
      727         'CUPID'
      899         'NEPTUNE'
      801         'TRITON'                NI
      802         'NEREID'                NII
      803         'NAIAD'                 NIII
      804         'THALASSA'              NIV
      805         'DESPINA'               NV
      806         'GALATEA'               NVI
      807         'LARISSA'               NVII
      808         'PROTEUS'               NVIII
      809         'HALIMEDE'
      810         'PSAMATHE'
      811         'SAO'
      812         'LAOMEDEIA'
      813         'NESO'
      999         'PLUTO'
      901         'CHARON'                PI
      902         'NIX'
      903         'HYDRA'
</PRE>
<BR><BR>
<A NAME="Spacecraft"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Spacecraft
</H3><P><BR><BR>
   THE SPICE convention uses negative integers as spacecraft ID codes. The
   code assigned to interplanetary spacecraft is normally the negative of
   the code assigned to the same spacecraft by JPL's Deep Space Network
   (DSN) as determined the NASA control authority at Goddard Space Flight
   Center.
<P>
 
   The current SPICE vehicle code assignments:
<P>
 
<PRE>
      NAIF ID     NAME
      ________    ____________________
      -1          'GEOTAIL'
      -5          'AKATSUKI'
      -5          'VCO'
      -5          'PLC'
      -5          'PLANET-C'
      -6          'P6'
      -6          'PIONEER-6'
      -7          'P7'
      -7          'PIONEER-7'
      -8          'WIND'
      -12         'VENUS ORBITER'
      -12         'P12'
      -12         'PIONEER 12'
      -13         'POLAR'
      -18         'MGN'
      -18         'MAGELLAN'
      -18         'LCROSS'
      -20         'P8'
      -20         'PIONEER-8'
      -21         'SOHO'
      -23         'P10'
      -23         'PIONEER-10'
      -24         'P11'
      -24         'PIONEER-11'
      -25         'LP'
      -25         'LUNAR PROSPECTOR'
      -27         'VK1'
      -27         'VIKING 1 ORBITER'
      -29         'STARDUST'
      -29         'SDU'
      -29         'NEXT'
      -30         'VK2'
      -30         'VIKING 2 ORBITER'
      -30         'DS-1'
      -31         'VG1'
      -31         'VOYAGER 1'
      -32         'VG2'
      -32         'VOYAGER 2'
      -40         'CLEMENTINE'
      -41         'MEX'
      -41         'MARS EXPRESS'
      -44         'BEAGLE2'
      -44         'BEAGLE 2'
      -46         'MS-T5'
      -46         'SAKIGAKE'
      -47         'PLANET-A'
      -47         'SUISEI'
      -47         'GNS'
      -47         'GENESIS'
      -48         'HUBBLE SPACE TELESCOPE'
      -48         'HST'
      -53         'MARS PATHFINDER'
      -53         'MPF'
      -53         'MARS ODYSSEY'
      -53         'MARS SURVEYOR 01 ORBITER'
      -55         'ULYSSES'
      -58         'VSOP'
      -58         'HALCA'
      -59         'RADIOASTRON'
      -61         'JUNO'
      -66         'VEGA 1'
      -67         'VEGA 2'
      -68         'MMO'
      -68         'MERCURY MAGNETOSPHERIC ORBITER'
      -69         'MPO'
      -69         'MERCURY PLANETARY ORBITER'
      -70         'DEEP IMPACT IMPACTOR SPACECRAFT'
      -74         'MRO'
      -74         'MARS RECON ORBITER'
      -76         'MSL'
      -76         'MARS SCIENCE LABORATORY'
      -77         'GLL'
      -77         'GALILEO ORBITER'
      -78         'GIOTTO'
      -79         'SPITZER'
      -79         'SPACE INFRARED TELESCOPE FACILITY'
      -79         'SIRTF'
      -81         'CASSINI ITL'
      -82         'CAS'
      -82         'CASSINI'
      -84         'PHOENIX'
      -85         'LRO'
      -85         'LUNAR RECON ORBITER'
      -85         'LUNAR RECONNAISSANCE ORBITER'
      -86         'CH1'
      -86         'CHANDRAYAAN-1'
      -90         'CASSINI SIMULATION'
      -93         'NEAR EARTH ASTEROID RENDEZVOUS'
      -93         'NEAR'
      -94         'MO'
      -94         'MARS OBSERVER'
      -94         'MGS'
      -94         'MARS GLOBAL SURVEYOR'
      -95         'MGS SIMULATION'
      -97         'TOPEX/POSEIDON'
      -98         'NEW HORIZONS'
      -107        'TROPICAL RAINFALL MEASURING MISSION'
      -107        'TRMM'
      -112        'ICE'
      -116        'MARS POLAR LANDER'
      -116        'MPL'
      -121        'BEPICOLOMBO'
      -127        'MARS CLIMATE ORBITER'
      -127        'MCO'
      -130        'MUSES-C'
      -130        'HAYABUSA'
      -131        'SELENE'
      -131        'KAGUYA'
      -135        'DRTS-W'
      -140        'EPOCH'
      -140        'DIXI'
      -140        'EPOXI'
      -140        'DEEP IMPACT FLYBY SPACECRAFT'
      -142        'TERRA'
      -142        'EOS-AM1'
      -146        'LUNAR-A'
      -150        'CASSINI PROBE'
      -150        'HUYGENS PROBE'
      -150        'CASP'
      -151        'AXAF'
      -151        'CHANDRA'
      -154        'AQUA'
      -159        'EUROPA ORBITER'
      -164        'YOHKOH'
      -164        'SOLAR-A'
      -165        'MAP'
      -166        'IMAGE'
      -177        'GRAIL-A'
      -178        'PLANET-B'
      -178        'NOZOMI'
      -181        'GRAIL-B'
      -183        'CLUSTER 1'
      -185        'CLUSTER 2'
      -187        'SOLAR PROBE'
      -188        'MUSES-B'
      -190        'SIM'
      -194        'CLUSTER 3'
      -196        'CLUSTER 4'
      -198        'INTEGRAL'
      -200        'CONTOUR'
      -202        'MAVEN'
      -203        'DAWN'
      -205        'SOIL MOISTURE ACTIVE AND PASSIVE'
      -205        'SMAP'
      -212        'STV51'
      -213        'STV52'
      -214        'STV53'
      -226        'ROSETTA'
      -227        'KEPLER'
      -228        'GLL PROBE'
      -228        'GALILEO PROBE'
      -234        'STEREO AHEAD'
      -235        'STEREO BEHIND'
      -236        'MESSENGER'
      -238        'SMART1'
      -238        'SM1'
      -238        'S1'
      -238        'SMART-1'
      -248        'VEX'
      -248        'VENUS EXPRESS'
      -253        'OPPORTUNITY'
      -253        'MER-1'
      -254        'SPIRIT'
      -254        'MER-2'
      -362        'RADIATION BELT STORM PROBE A'
      -362        'RBSP_A'
      -363        'RADIATION BELT STORM PROBE B'
      -363        'RBSP_B'
      -486        'HERSCHEL'
      -489        'PLANCK'
      -500        'RSAT'
      -500        'SELENE Relay Satellite'
      -500        'SELENE Rstar'
      -500        'Rstar'
      -502        'VSAT'
      -502        'SELENE VLBI Radio Satellite'
      -502        'SELENE VRAD Satellite'
      -502        'SELENE Vstar'
      -502        'Vstar'
      -550        'MARS-96'
      -550        'M96'
      -550        'MARS 96'
      -550        'MARS96'
</PRE>
<BR><BR>
<A NAME="Earth Orbiting Spacecraft."></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Earth Orbiting Spacecraft.
</H3><P><BR><BR>
   If an Earth orbiting spacecraft lacks a DSN identification code, the
   NAIF ID is derived from the tracking ID assigned to it by the US Space
   Command via:
<P>
 
<PRE>
      NAIF ID = -100000 - US Space Command code
</PRE>
   For example US Space Command assigned the code 15427 to the NOAA 9
   spacecraft. This code corresponds to the NAIF ID -115427.
<P>
 
<BR><BR>
<A NAME="Comet Shoemaker Levy 9"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Comet Shoemaker Levy 9
</H3><P><BR><BR>
   In July, 1992 Comet Shoemaker Levy 9 passed close enough to the planet
   Jupiter that it was torn apart by gravitational tidal forces. As a
   result it became a satellite of Jupiter. However, in July 1994 the
   remnants of Shoemaker Levy 9 collided with Jupiter. Consequently, the
   fragments existed as satellites of Jupiter for only two years. These
   fragments were given the NAIF ID's listed below. Unfortunately, there
   have been two competing conventions selected for identifying the
   fragments of the comet. In one convention the fragments have been
   assigned numbers 1 through 21. In the second convention the fragments
   have been assigned letters A through W (with I and O unused). To add to
   the confusion, the ordering for the numbers is reversed from the letter
   ordering. Fragment 21 corresponds to letter A; fragment 20 to letter B
   and so on. Fragment A was the first of the fragments to collide with
   Jupiter; fragment W was the last to collide with Jupiter.
<P>
 
   The original fragments P and Q subdivided further creating the fragments
   P2 and Q1.
<P>
 
<PRE>
      NAIF ID     NAME                    SHOEMAKER-LEVY 9 FRAGMENT
      ________    ____________________    _________________________
      50000001    'SHOEMAKER-LEVY 9-W'    FRAGMENT 1
      50000002    'SHOEMAKER-LEVY 9-V'    FRAGMENT 2
      50000003    'SHOEMAKER-LEVY 9-U'    FRAGMENT 3
      50000004    'SHOEMAKER-LEVY 9-T'    FRAGMENT 4
      50000005    'SHOEMAKER-LEVY 9-S'    FRAGMENT 5
      50000006    'SHOEMAKER-LEVY 9-R'    FRAGMENT 6
      50000007    'SHOEMAKER-LEVY 9-Q'    FRAGMENT 7
      50000008    'SHOEMAKER-LEVY 9-P'    FRAGMENT 8
      50000009    'SHOEMAKER-LEVY 9-N'    FRAGMENT 9
      50000010    'SHOEMAKER-LEVY 9-M'    FRAGMENT 10
      50000011    'SHOEMAKER-LEVY 9-L'    FRAGMENT 11
      50000012    'SHOEMAKER-LEVY 9-K'    FRAGMENT 12
      50000013    'SHOEMAKER-LEVY 9-J'    FRAGMENT 13
      50000014    'SHOEMAKER-LEVY 9-H'    FRAGMENT 14
      50000015    'SHOEMAKER-LEVY 9-G'    FRAGMENT 15
      50000016    'SHOEMAKER-LEVY 9-F'    FRAGMENT 16
      50000017    'SHOEMAKER-LEVY 9-E'    FRAGMENT 17
      50000018    'SHOEMAKER-LEVY 9-D'    FRAGMENT 18
      50000019    'SHOEMAKER-LEVY 9-C'    FRAGMENT 19
      50000020    'SHOEMAKER-LEVY 9-B'    FRAGMENT 20
      50000021    'SHOEMAKER-LEVY 9-A'    FRAGMENT 21
      50000022    'SHOEMAKER-LEVY 9-Q1'   FRAGMENT 7A
      50000023    'SHOEMAKER-LEVY 9-P2'   FRAGMENT 8B
</PRE>
<BR><BR>
<A NAME="Comets"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Comets
</H3><P><BR><BR>
   ID codes for periodic comets begin at 1000001 and continue in sequence
   indefinitely. (The current numbering scheme assumes that no need for
   more than one million comet ID codes.) The current list of periodic
   comets and their ID codes are given below. As new periodic comets are
   discovered, this list will be expanded. The ID codes for a new comet
   will be formed by adding one to the last comet ID in the current SPICE
   list. As you can see the first portion of the list is in alphabetical
   order. However, this pattern breaks down at ID code 1000112. This
   reflects the fact that new periodic comets were discovered after
   identification of the first 111. If you don't find the comet you are
   interested in the first 111 comets listed look at the last 28 to see if
   you can find the comet of interest.
<P>
 
   Finally, note that Comet Shoemaker Levy 9 is included in this list (ID
   code 1000130) though it is no longer a comet, periodic or otherwise. It
   was an identified periodic comet prior to its breakup, which accounts
   for its inclusion in this list.
<P>
 
<PRE>
      NAIF ID     NAME
      ________    ____________________
      1000001     'AREND'
      1000002     'AREND-RIGAUX'
      1000003     'ASHBROOK-JACKSON'
      1000004     'BOETHIN'
      1000005     'BORRELLY'
      1000006     'BOWELL-SKIFF'
      1000007     'BRADFIELD'
      1000008     'BROOKS 2'
      1000009     'BRORSEN-METCALF'
      1000010     'BUS'
      1000011     'CHERNYKH'
      1000012     '67P/CHURYUMOV-GERASIMENKO (1969 R1)'
      1000012     'CHURYUMOV-GERASIMENKO'
      1000013     'CIFFREO'
      1000014     'CLARK'
      1000015     'COMAS SOLA'
      1000016     'CROMMELIN'
      1000017     'D''ARREST'
      1000018     'DANIEL'
      1000019     'DE VICO-SWIFT'
      1000020     'DENNING-FUJIKAWA'
      1000021     'DU TOIT 1'
      1000022     'DU TOIT-HARTLEY'
      1000023     'DUTOIT-NEUJMIN-DELPORTE'
      1000024     'DUBIAGO'
      1000025     'ENCKE'
      1000026     'FAYE'
      1000027     'FINLAY'
      1000028     'FORBES'
      1000029     'GEHRELS 1'
      1000030     'GEHRELS 2'
      1000031     'GEHRELS 3'
      1000032     'GIACOBINI-ZINNER'
      1000033     'GICLAS'
      1000034     'GRIGG-SKJELLERUP'
      1000035     'GUNN'
      1000036     'HALLEY'
      1000037     'HANEDA-CAMPOS'
      1000038     'HARRINGTON'
      1000039     'HARRINGTON-ABELL'
      1000040     'HARTLEY 1'
      1000041     'HARTLEY 2'
      1000042     'HARTLEY-IRAS'
      1000043     'HERSCHEL-RIGOLLET'
      1000044     'HOLMES'
      1000045     'HONDA-MRKOS-PAJDUSAKOVA'
      1000046     'HOWELL'
      1000047     'IRAS'
      1000048     'JACKSON-NEUJMIN'
      1000049     'JOHNSON'
      1000050     'KEARNS-KWEE'
      1000051     'KLEMOLA'
      1000052     'KOHOUTEK'
      1000053     'KOJIMA'
      1000054     'KOPFF'
      1000055     'KOWAL 1'
      1000056     'KOWAL 2'
      1000057     'KOWAL-MRKOS'
      1000058     'KOWAL-VAVROVA'
      1000059     'LONGMORE'
      1000060     'LOVAS 1'
      1000061     'MACHHOLZ'
      1000062     'MAURY'
      1000063     'NEUJMIN 1'
      1000064     'NEUJMIN 2'
      1000065     'NEUJMIN 3'
      1000066     'OLBERS'
      1000067     'PETERS-HARTLEY'
      1000068     'PONS-BROOKS'
      1000069     'PONS-WINNECKE'
      1000070     'REINMUTH 1'
      1000071     'REINMUTH 2'
      1000072     'RUSSELL 1'
      1000073     'RUSSELL 2'
      1000074     'RUSSELL 3'
      1000075     'RUSSELL 4'
      1000076     'SANGUIN'
      1000077     'SCHAUMASSE'
      1000078     'SCHUSTER'
      1000079     'SCHWASSMANN-WACHMANN 1'
      1000080     'SCHWASSMANN-WACHMANN 2'
      1000081     'SCHWASSMANN-WACHMANN 3'
      1000082     'SHAJN-SCHALDACH'
      1000083     'SHOEMAKER 1'
      1000084     'SHOEMAKER 2'
      1000085     'SHOEMAKER 3'
      1000086     'SINGER-BREWSTER'
      1000087     'SLAUGHTER-BURNHAM'
      1000088     'SMIRNOVA-CHERNYKH'
      1000089     'STEPHAN-OTERMA'
      1000090     'SWIFT-GEHRELS'
      1000091     'TAKAMIZAWA'
      1000092     'TAYLOR'
      1000093     'TEMPEL_1'
      1000093     'TEMPEL 1'
      1000094     'TEMPEL 2'
      1000095     'TEMPEL-TUTTLE'
      1000096     'TRITTON'
      1000097     'TSUCHINSHAN 1'
      1000098     'TSUCHINSHAN 2'
      1000099     'TUTTLE'
      1000100     'TUTTLE-GIACOBINI-KRESAK'
      1000101     'VAISALA 1'
      1000102     'VAN BIESBROECK'
      1000103     'VAN HOUTEN'
      1000104     'WEST-KOHOUTEK-IKEMURA'
      1000105     'WHIPPLE'
      1000106     'WILD 1'
      1000107     'WILD 2'
      1000108     'WILD 3'
      1000109     'WIRTANEN'
      1000110     'WOLF'
      1000111     'WOLF-HARRINGTON'
      1000112     'LOVAS 2'
      1000113     'URATA-NIIJIMA'
      1000114     'WISEMAN-SKIFF'
      1000115     'HELIN'
      1000116     'MUELLER'
      1000117     'SHOEMAKER-HOLT 1'
      1000118     'HELIN-ROMAN-CROCKETT'
      1000119     'HARTLEY 3'
      1000120     'PARKER-HARTLEY'
      1000121     'HELIN-ROMAN-ALU 1'
      1000122     'WILD 4'
      1000123     'MUELLER 2'
      1000124     'MUELLER 3'
      1000125     'SHOEMAKER-LEVY 1'
      1000126     'SHOEMAKER-LEVY 2'
      1000127     'HOLT-OLMSTEAD'
      1000128     'METCALF-BREWINGTON'
      1000129     'LEVY'
      1000130     'SHOEMAKER-LEVY 9'
      1000131     'HYAKUTAKE'
      1000132     'HALE-BOPP'
</PRE>
<BR><BR>
<A NAME="Asteroids"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Asteroids
</H3><P><BR><BR>
   ID codes for numbered asteroids listed in the JPL Asteroid and Comet
   Catalog [166.0] are determined via the algorithm:
<P>
 
<PRE>
      NAIF ID code = 2000000 + JPL Asteroid number
</PRE>
   For example, asteroid Yeomans (2956) has NAIF ID number 2002956. The
   complete list of asteroids is far too numerous (over 4000 identified
   asteroids) to include in this document. However, we include the NAIF ID
   codes for the most commonly requested asteroids:
<P>
 
<PRE>
      NAIF ID     NAME
      ________    ____________________
      9511010     'GASPRA'
      2431010     'IDA'
      2431011     'DACTYL'
      2000001     'CERES'
      2000004     'VESTA'
      2000021     'LUTETIA'
      2000216     'KLEOPATRA'
      2000433     'EROS'
      2000253     'MATHILDE'
      2002867     'STEINS'
      2009969     '1992KD'
      2009969     'BRAILLE'
      2004015     'WILSON-HARRINGTON'
      2004179     'TOUTATIS'
      2025143     'ITOKAWA'
</PRE>
   There are three exceptions to the rule---asteroids Gaspra, Ida and Ida's
   satellite Dactyl, visited by the Galileo spacecraft. The ID codes for
   these asteroids were determined using an older numbering convention now
   abandoned by the SPICE system.
<P>
 
   The orbit of Dactyl has not been completely determined at the time of
   this writing. However, in anticipation of this determination, Dactyl has
   been assigned the NAIF ID code 2431011.
<P>
 
   Note that if more than 431010 asteroids are ever identified and
   cataloged there will arise a conflict between the new numbering system
   and the ID code for Ida. At that time NAIF (or its successor) will need
   to add another exception to the asteroid numbering system.
<P>
 
<BR><BR>
<A NAME="Ground Stations."></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Ground Stations.
</H3><P><BR><BR>
   The SPICE system accommodates ephemerides for tracking stations and
   landed spacecraft. Currently five earth tracking station sites are
   supported: Goldstone, Canberra, Madrid, Usuda, and Parkes. Note that
   these refer only to the general geographic location of the various
   tracking sites. IDs for the individual antennas at a given site are
   assigned when more than one antenna is present.
<P>
 
   The following NAIF ID codes are assigned.
<P>
 
<PRE>
      NAIF ID     NAME
      ________    ____________________
      398989      'NOTO'
      398990      'NEW NORCIA'
      399001      'GOLDSTONE'
      399002      'CANBERRA'
      399003      'MADRID'
      399004      'USUDA'
      399005      'DSS-05'
      399005      'PARKES'
      399012      'DSS-12'
      399013      'DSS-13'
      399014      'DSS-14'
      399015      'DSS-15'
      399016      'DSS-16'
      399017      'DSS-17'
      399023      'DSS-23'
      399024      'DSS-24'
      399025      'DSS-25'
      399026      'DSS-26'
      399027      'DSS-27'
      399028      'DSS-28'
      399033      'DSS-33'
      399034      'DSS-34'
      399042      'DSS-42'
      399043      'DSS-43'
      399045      'DSS-45'
      399046      'DSS-46'
      399049      'DSS-49'
      399053      'DSS-53'
      399054      'DSS-54'
      399055      'DSS-55'
      399061      'DSS-61'
      399063      'DSS-63'
      399064      'DSS-64'
      399065      'DSS-65'
      399066      'DSS-66'
</PRE>
<BR><BR>
<A NAME="Inertial and Non-inertial Reference Frames"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H3> Inertial and Non-inertial Reference Frames
</H3><P><BR><BR>
   Please refer to the Frames Required Reading document, <a href="../req/frames.html">frames.req</a>, for
   detailed information on the implementation of reference frames in the
   SPICE system.
<P>
 
<BR><BR>
<A NAME="Spacecraft Clocks."></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Spacecraft Clocks.
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   The ID code used to identify the on-board clock of a spacecraft
   (spacecraft clock or SCLK) in SPICE software is the same as the ID code
   of the spacecraft. This convention assumes that only one clock is used
   on-board a spacecraft to control all observations and spacecraft
   functions. However, missions are envisioned in which instruments may
   have clocks not tightly coupled to the primary spacecraft control clock.
   When this situation occurs, the correspondence between clocks and
   spacecraft will be broken and more than one clock ID code will be
   associated with a mission. It is anticipated that the I-kernel will
   contain the information needed to associate the appropriate clock with a
   particular instrument.
<P>
 
<BR><BR>
<A NAME="Instruments"></A>
<p align="right"><a href="#top"><small>Top</small></a></p>
<H2> Instruments
</H2><HR ALIGN="LEFT" WIDTH=50% ><P><BR><BR>
   With regards to a spacecraft, the term ``instrument'' means a science
   instrument or vehicle structure to which the concept of orientation is
   applicable.
<P>
 
   NAIF, in cooperation with the science teams from each flight project,
   assigns ID codes to a vehicle instrument. The instruments are simply
   enumerated via some project convention to arrive at an ''instrument
   number.'' The NAIF ID code for an instrument derives from the instrument
   number via the function:
<P>
 
<PRE>
      NAIF instrument code = (s/c code)*(1000) - instrument number
</PRE>
   This allows for 1000 instrument assignments on board a spacecraft. An
   application of the instrument ID concept applied to the Voyager 2
   vehicle (ID -32):
<P>
 
<UL>
<TT>&#32;&#32;</TT> -32000 -&gt; Instrument Scan Platform
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32001 -&gt; ISSNA (Imaging science narrow angle camera)
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32002 -&gt; ISSWA (Imaging science wide angle camera)
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32003 -&gt; PPS (Photopolarimeter)
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32004 -&gt; UVSAG (Ultraviolet Spectrometer, Airglow port)
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32005 -&gt; UVSOCC (Ultraviolet Spectrometer, Occultation port)
<BR><BR></UL>
<UL>
<TT>&#32;&#32;</TT> -32006 -&gt; IRIS (Infrared Interferometer Spectrometer and Radiometer)
<BR><BR></UL>
   Use SPICE text kernels (usually Instrument or Frames kernels) to define
   the instrument name/ID mappings.
<P>
 

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